The Helldivers 2 community was ready for an all-out assault after Arrowhead announced that Illuminate was coming in the Omens of Tyranny update. With retired Helldivers rejoining the effort, Super Earth pushed back the initial attack by a day. However, despite bracing for a massive second wave attack, none came.

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Helldivers 2 was once an uplifting and supportive live-action gem, but since launch, the community has become the center of outrage.
Light has contented itself with skirmishes on the outer fringes of the galaxy, with relatively light forces, which sometimes seem easier to overturn than the Terminids. That, whatever is building in the Meridia Black Hole, players are feeling something off. While there are a bunch of theories floating around, one we've seen on Reddit is the coolest.
Light is not the real enemy
Simply put, the theory put forward by Ryukage06 is that the Illuminati are not attacking, they are fleeing. After being completely destroyed in the First Galactic War, an advanced species like the Illuminati would know better than to attack a Super Earth with such a degenerate force. They speculate that the Illuminate is actually running from a greater threat to its existence than the Super Earth itself.
The theory suggests that this unknown enemy has taken advantage of the Illuminati's weakened state after the First War, forcing them to either flee with what little power they have left or lure this enemy into an all-out war with Super Earth.
As for who or what this potential enemy is, they speculate that it could be “some kind of bio-horror, like the Flood from Halo, or the Thing from John Carpenter's '80s sci-fi horror. [classic]. It would be easier for the devs to make this enemy into the game, as they would only need to redesign/reskin the existing enemies to look like horribly mutated versions of the original.”
Of course, this is all speculation, but Ryukage06 has backed up their theories with some pointers that you can see in a Reddit post.
Another potential new faction that players have speculated about is a race inspired by HP Lovecraft's cosmic horror. Literally ancient demonic enemies like Cthulhu and his minions can drop a 500Kg bomb making for a fresh and interesting new enemy.
Whatever this potential new enemy may be, you can be sure that it will never shake our freedom or take away our freedom.

Hell Diver 2
Galaxy's Last Line of Offense. Enroll in Helldivers and join the fight for freedom in a hostile galaxy in a fast, frantic, and brutal third-person shooter. Helldivers 2 features Arrowhead's best cooperative gameplay yet. Collaboration will be essential: teams will coordinate loadouts, strategize their approach to each mission, and accomplish objectives together.